> As a sysadmin, I would not want my /bin /sbin exposed to everyone.
Why not? It's not like most of them are suid (right?). Most Unix systems I've used allow any user to peruse /sbin at their leisure and run whatever they want.
>>digita+MQ
Yes of course, just like on more or less any Linux system. But IIRC, shutdown is a suid binary that will do its own permission checks while running. The permissions on the /sbin/ directory should not matter.